1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a valve unit for closing a flow path of a fluid and timely opening the flow path such that the fluid flows along a channel, a reaction apparatus with the same, and a method of forming a valve for opening and closing a flow path of a fluid in a channel.
2. Description of the Related Art
A minute channel constituting a flow path for a fluid is formed in a substrate (i.e., a lab-on-a-chip) used for a biochemical reaction, for example, a lysis reaction or polymerase chain reaction (PCR). A valve unit that closes the minute channel such that the fluid cannot flow and timely opens the minute channel to allow the fluid to flow may be provided in the substrate.
A substrate for a biochemical reaction introduced in Anal. Chem. Vol. 76, p. 1824˜1831, 2004 and another substrate for a biochemical reaction introduced in the same article, pp. 3740˜3748 are provided with a valve formed of only paraffin wax, and provided with a heating member for melting the paraffin wax. However, a large amount of paraffin wax is needed to close the minute channel, and a large sized heating member is needed to melt the large amount of paraffin wax, which make it difficult to miniaturize and integrate a substrate for a biochemical reaction. Also, the melting process of the paraffin wax takes a lot of heating time and it is difficult to accurately control a point of time at which the channel is opened.